This invention relates to detergent compositions and methods of forming detergent compositions. The detergent compositions formed have greatly improved soil removal and/or anti-redeposition properties. These properties have been found to be unexpectedly improved by the addition of a modified vegetable protein material which provides greatly improved and unexpected anti-redeposition properties. Further, the modified vegetable protein material is rapidly biodegradable, thus significantly improving the environmental properties of the detergent as a whole.
Applicants are aware of the following U.S. Pat. Nos., the disclosures of which are incorporated by reference herein.
U.S. Pat. No. 3,000,830 PA0 U.S. Pat. No. 3,594,324 PA0 U.S. Pat. No. 4,352,692 PA0 U.S. Pat. No. 4,474,694 PA0 U.S. Pat. No. 4,689,381
Synthetic detergent compositions have been used commercially for many years for the removal of soil from fabric. These materials generally are combinations of a number of different compounds or additives. These compositions may include, although they are not necessarily limited to, an organic detergent compound such as a surfactant or surface active agent, builder components such as a phosphate salt which enhances the cleaning effectiveness of the surfactant by sequestering various metal ions found in hard water and also a soil suspending or anti-redeposition agent to help the surfactant hold the soil particles in suspension and prevent them from being redeposited onto the fabric during washing.
The use of a soil anti-redeposition agent generally improves the whiteness of fabrics washed with the detergent or the brightness of the color, since the anti-redeposition agent suspends the soil in the solution once it has been removed from the fabric and prevents its redeposition onto the washed fabric. If the detergent composition has poor soil suspension properties during washing and the soil is allowed to be redeposited or to settle from the wash water onto the washed fabric, the fabric will eventually acquire a gray or dull appearance, which is extremely undesirable aesthetically.
A number of materials have been used as soil anti-redeposition agents. One of the most widely used materials is carboxymethylcellulose. Carboxymethylcellulose has been added for a number of years to different types of detergent compositions used for washing fabrics to prevent redeposition of soil from solution once the soil has been removed from the fabric by washing. Other materials which have been proposed or used as soil anti-redeposition agents include sodium polyacrylate, polyvinyl acetate, ethylcelluloses, polyvinyl alcohols, sodium alginate and various modified starches. All of the above are generally regarded as being less effective than carboxymethylcellulose. Other types of soil anti-redeposition agents which have been described as having improved soil anti-redeposition properties over carboxymethylcellulose include polyvinylpyrrolidone, as described in U.S. Pat. No. 3,000,830, and a combination of carboxymethylcellulose and a gelatin protein as described in U.S. Pat. No. 3,594,324. While use of these materials as soil anti-redeposition agents in detergents has been somewhat successful, none the less, a need still exists for an improved material having better soil anti-redeposition properties and one which is readily adaptable and useful in a wide variety of detergent compositions. It is particularly desirable to develop a soil anti-redeposition agent which is more effective in liquid detergent compositions. Carboxymethylcellulose and ethylcelluloses, for example, and other state of the art redeposition agents, typically have very poor solubility in the solutions which make up liquid detergent compositions. As a result, these materials have very low effectiveness as soil anti-redeposition agents in liquid detergent compositions.
Applicants have found that a modified soy protein material, particularly a modified soy protein material which incorporates a cationic monomer, and in particular cationic chlorohydrin, epoxy and/or acrylate monomers, have unexpected soil anti-redeposition properties. Anionic soy protein which has ben carboxylated is also effective as a soil anti-redeposition agent. These soil anti-redeposition properties are observable when the material is used in liquid detergent compositions or in dry powdered detergent compositions. Moreover, these modified soy protein materials exhibit an unexpected improvement in soil anti-redeposition properties in many detergent systems. Applicants, anti-redeposition materials are effective in liquid and powdered detergents and in detergents used in cool and hot water. Applicants, anti-redeposition materials are effective when used with a variety of conventional washing detergent materials, including surfactants, builders and additives. Applicants, anti-redeposition materials are effective on a wide variety of soils and for a wide variety of fabrics.
It is therefore an object of the present invention to provide a method of improving the soil anti-redeposition properties of detergent compositions.
It is a further object of the present invention to provide a detergent composition which has greatly improved soil anti-redeposition properties.
It is also an object of the present invention to provide a method of improving the soil anti-redeposition properties of detergent materials by incorporating a modified soy protein compound in the detergent composition.
It is an object of this invention to improve the biodegradable properties of washing detergents.
It is an object of this invention to provide an anti-redeposition agent, for washing detergents, which is biodegradable.
It is an object of this invention to provide a modified protein soil anti-redeposition agent for washing detergents.
It is an object of this invention to provide an ionically modified soil anti-redeposition agent for washing detergents.
It is an object of this invention to provide cationically and anionically modified soy protein soil anti-redeposition agents for washing detergents and to provide a method using such soil anti-redeposition agents.
These and other objects will be apparent from the following Description of the Preferred Embodiments.